Chalcopyrite Flotation: A Comprehensive Review with Emphasis on Pyrite Separation

Abstract

Froth flotation is the most widely employed technique for the beneficiation of chalcopyrite. However, the declining ore grades and increasing pyrite content in feedstocks pose significant challenges in achieving high-purity chalcopyrite concentrates. Although chalcopyrite exhibits inherently higher hydrophobicity than pyrite, this advantage gets diminished in practical flotation due to galvanic interactions, surface oxidation, and the strong influence of pulp chemistry. This review provides a comprehensive analysis of the solubility and electrokinetic characteristics of chalcopyrite and pyrite, the adsorption behavior of various surfactants, and emerging strategies for their efficient separation. Though conventional collectors such as xanthates (X), dithiophosphates (DTPs), and dithiocarbamates (DTCs) are being broadly used in chalcopyrite flotation, their performances have been increasingly compromised by elevated pyrite content, prompting the development of new-age collectors with enhanced chelating and coordinating abilities. Therefore, the present communication provides an overview of many novel collectors vis-& agrave;-vis their performances with the conventional ones. Besides, the role of conventional and modified depressants, including polysaccharides, amino acid derivatives, sulfur-based compounds, and inorganic oxidants, is critically examined for their effectiveness in selectively depressing pyrite. The present review aims to provide insights vital for improving the separation efficiency of chalcopyrite - pyrite flotation systems.